Implications of H-alpha Observations for Studies of the Cosmic Microwave Background

P. R. McCullough; J. E. Gaustad; W. Rosing; D. Van Buren

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Implications of H-alpha Observations for Studies of the Cosmic Microwave Background

P. R. McCullough·J. E. Gaustad·W. Rosing·D. Van Buren

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Abstract

We summarize the relationship between the free-free emission foreground and Galactic H-alpha emission. H-alpha observations covering nearly the entire celestial sphere are described. These data provide a template to isolate and/or remove the effect of Galactic free-free emission from observations of the cosmic microwave background. Spectroscopy and imaging provide two complementary methods for measuring the H-alpha emission. Spectroscopy is favored for its velocity resolution and imaging is favored for its angular resolution. With templates of the three dominant foregrounds, namely synchrotron, thermal dust, and free-free emissions, it may be possible to quantify the location and the brightness of another foreground such as that from rotating dust grains.

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P. R. McCullough, J. E. Gaustad, W. Rosing, D. Van Buren. 1999-02-17. Implications of H-alpha Observations for Studies of the Cosmic Microwave Background. https://arxiv.org/abs/astro-ph/9902248

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